1. Field of the Invention
The present invention relates to architectural building blocks and more particularly to a new and improved lightweight, architectural building block formed of light transmitting, molded plastic material having a thin, hard, transparent, abrasion resistant surface coating of plastic resin permanently bonded on at least one side face of the block.
The lightweight, molded plastic building block of the present invention provides a number of important features and advantages over conventional glass building blocks and these features include: (1) weight reduction of 50% to 75%; (2) high impact resistance against external and internal forces; (3) the plastic block is nearly indestructible in normal or abusive situations; (4) some 250 times stronger than an ordinary glass block; (5) 20% to 30% improved thermal efficiency over that of a glass block; (6) an optical quality equal to or better than that of a glass block; (7) provides increased security and safety; (8) unlimited color and tint selections are available; (9) detachable snap lock connector assemblies eliminate the need for skilled labor in assembling or building structures made up of the blocks; (10) RTV silicone and other adhesives can be utilized in place of conventional mortar joints, thereby eliminating the need for special tools and masonry skills; (11) decorative features including relatively low cost interior surfaces of gold, silver and other metals can be provided easily by vacuum deposition, sputtering, etc.; (12) unlimited graphics and indicia are readily obtainable in molded form on outer surfaces including company logos, initials, special designs and shapes which can be economically produced; and (13) the interior of the block is readily illuminated for decorative and/or security needs.
A new and improved architectural building block in accordance with the present invention is produced in a low stress, injection molding process of the type more fully described and set forth in copending U.S. patent application Ser. No. 07/389,338, filed Aug. 3, 1989 for a PANEL AND METHOD OF MAKING THE SAME, which patent application is hereby incorporated herein by reference.
2. Background of the Prior Art
Over the years, a wide variety of architectural building blocks commonly known as glass blocks or glass bricks have been developed for use in exterior walls, interior walls and/or other types building structures. Austrian Patent Nos. 169151 and 183209, Belgian Patent No. 567594, Canadian Patent No. 712300, French Patent Nos. 1155005, 1186063, 1196461 and 1341653 and U.S. Pat. Nos. 951,010, 2,170,602, 2,194,756, 3,387,421, 3,422,588, 3,438,165, 3,798,861, 3,954,326, 4,004,392, 4,628,652 and 4,852,321 generally disclose glass blocks or glass bricks used for buildings and the like, having one or more drawbacks in that they are relatively heavy, easy to break, low in strength, easily damaged and have generally poor heat insulating or heat transfer characteristics.